current location of Samoan hotspot; just N of Lau Basin (SW Pacific); summit crater is 400-m deep and 2-km wide with new volcanic cone Nafanua in center; "Moat of Death" at base of Nafanua; temperatures up to 81 C in 2005; Staudigel et al. (2004): "The turbidity of the ocean water reaches 1.4 NTU, values that are higher than in any other submarine hydrothermal system."; located just west of the U.S. Rose Atoll Marine National Monument